Dental fastening for removable bridges and bridge-plates



c. w. LOKEY.

DENTAL FASTENING FOR REMOVABLE BRIDGES AND BRIDGE PLATES.

APPLICATION FILED OCT. 22, 1914. RENEWED DEC. 29.1915.

1 ,1 93,U3%, Patented Aug. 1, 1916.

CHARLES W. LOKEY, OF BIRMINGHAM, ALABAMA.

riaaosa.

Specification of Letters Patent.

Patented Aug. ii, 191%.

Application filed October 22, 1914, Serial No. 868,034. Renewed December 29, 1915. Serial No. 69,264.

To all whom it may concern Be it known that I, CHARLES W. LOKEY, a citizen of the United States of America, residing at Birmingham, in the county of Jefferson and State of Alabama, have invented certain new and useful Improvements in Dental Fastenings for Removable Bridges and Bridge-Plates, of which the following is a specification.

My invention relates to dental fastenings for removable bridges and bridge plates and my object is to provide a small compact and very strong fastening which is adapted to occupy a minimum space between the abutment and the teeth to be replaced so as to avoid undue cutting away of the latter.

In its preferred embodiment, my invention comprises a keeper, formed of hard metal shaped to provide side grooves and preferably a top groove alining with the side grooves, and an anchor attachment for the removable bridge or bridge plate, which is formed of bent wire (preferably drawn wire of hard metal such as irridio platinum) that is shaped to fit snugly into the grooves of the keeper and to interlock firmly therewith so that the fastening resists with much strength any relative movement between the keeper and anchor except in the direction in which the bridge or bridge plate is moved to detach it from the abutment.

My invention further comprises the novel details of construction and arrangements of parts which in their preferred embodiments are hereinafter more particularly described and claimed, reference being had to the accompanying drawings which form a part of this specification, and in which Figure 1 is a plan view illustrating the lower jaw with a bridge plate attached by my improved fastening. Fig. 2 is a similar view of the jaw with the bridge plate removed showing the keepers attached to the abutments. Fig. 3 illustrates the bridge plate and anchors therefor in plan View. Fig. 4: is a detail View of an abutment with the keeper attached. Fig. 5 is an enlarged sectional view through the keeper and abutment showing an anchor in position. Fig. 6 is a detail perspective view of the keeper detached. Fig. 7 is a sectional view taken on the line a"w of Fig. 3, showing the anchor in front elevation. Fig. 8 is a detail view illustrating the preferred form of anchor. Figs. 9 and 10 illustrate modified forms of anchors.

Similar reference numerals refer to simi lar parts throughout the drawings.

The lower jaw illustrated is provided with an abutment 1 on each side. The abutments may be of any suitable construction and attached to any desired tooth as each case may require.

My improved keeper is formed of a block of hard metal rolled or shaped so as to provide it with longitudinal grooves in its opposite side edges, which grooves leave a thickened front face 2 connected by a web 3 with a thin back face 4, which face is adapted to be soldered to the abutment and is made as thin as is consistent with the strength required for its attachment to the abutment. The web 3 is preferably cut away below the top edges of the keeper faces so as to form what may be termed a top groove across the keeper.

The anchor, which is adapted to engage and interlock with the keeper to hold the bridge or bridge plate firmly attached to the abutment, may be formed in several ways, the preferred form being illustrated in Fig. 8, wherein a drawn wire of hard metal is bent at the center to form a narrow upright eye 5 while its ends are out-turned from the base of the eye at 6 and then bent rearwardly at right angles to the eye and in parallelism to form the ends 7. These ends are intended to be made fast in the rubber of the saddle 8 as shown in Fig. 7, or they may be attached in any suitable manner to a metal saddle or to the bridge or bridge plate, as conditions may require. The eye 5 in the anchor is made just wide enough to slip over the web 3 and fit snugly into the side and top grooves of the keeper. In practice, the eye is adapted to grip tightly against the sides of the web and hold the bridge or bridge plate tightly interlocked with the abutment and removable therefrom only by endwise movement along the web. In Fig. 9 the anchor is formed with only one leg 7, this arrangement being desirable under certain conditions where space or convenience of attachment make it preferable to use only one retaining leg for the anchor. In Fig. 10 the formation of the anchor is reversed, the loop portion 8 thereof which is made fast to the saddle or plate being U- shaped with its ends drawn in at 9 and bent upwardly at 10. The ends 10 in this case fit into the side grooves of the keeper and clamp against the sides of the web 3 of the keeper. WVhen this type of anchor is used 7 it is not necessary for the web to be cut out.

down below the top edges of the keeper faces, to make provision for the settling of the bridge. Tov provide for the settling of the bridge or bridge plate where the anchor shown in v 7 Figs. 8 or 9 is used, I file down the top groove 'in the web 3, but where the anchor shown in Fig. '10 is used, the fact that the loop is notclosed over-the web permits the anchor to settle freely.

The elongated character of the interlock obtained between the anchor and keeper enables the fastening to hold the bridge or bridge plate against any tendency to turn about the keeper and by forming the keeper so that its side grooves provide a snug fit for the sides of the anchor, any tendency of the fastening to rattle or work loose is minimized. I

When the ends 7 are vulcanized into a rubber saddle, it will be understood that in accordance With the present general practice these ends are bent or have cross pieces attached thereto to prevent anchor pulling In the form shown, bars 11 are provided to connect the different sections of the bridge plate.

Thesides of the eye 5 can be pinched together to make them fit with the desired frictional grip against the web 2'. 6., to have length enough to provide sufficient side bearings for the anchor to prevent the latter turning or pivoting on the keeper.

While Iprefer the keeper to have substantial length, yet this is not entirely essential as the anchor would interlock effectively with a body presenting the desired side grooves to receive the eye of the anchor.

Having thus described my invention, what I claim as new and desire-to secure by Let: ters Patent, is

1. In a dental fastening, in combination, a keeper formed with an outwardly facing groove extending up each ofits opposite side faces, and an anchor of bent metal adapted J in its opposite side faces longitudinal grooves which shape the body into front and back walls connected by a longitudinal and relatively narrow central web.

3. In a dental fastening, a keeper formed of an elongated body of hard metal having in its faces longitudinal grooves which shape the body into front and back walls connected'by a longitudinal and relatively narrow central web, said web being cut away below the top edges of said walls to form a groove across the top of the keeper.

4. A dental fastening for detachably securing'a bridge or bridge plate toa permanent abutment tooth comprising in combination a keeper having longitudinal outwardly facing grooves on its side faces shaped to receive a wire forming an anchor, and an anchor formed of bent wire having closely spaced members adapted to be adjusted toward and from each and to yieldingly engage in the longitudinal grooves of the keeper for. endwise removal therefrom.

5. In a dental fastening for removable bridges and bridge plates, in combination, a keeper formed of an elongated hard metal bar having grooves extending lengthwise of its'opposite narrow side faces, said grooves being disposed closer tothe rear than to the front face of the keeper and being curved in cross-sectional contour, and an anchor having means for attachment to the bridge or bridge plate and having wire arins which ]01Il overhead and are adapted to be sprung over the grooved side faces 'of the keeper and to fit snugly into said grooves and to engage the top thereof, substantially as described.

6. In a dental fastening, an anchor formed of hard metal wire having a portion thereof adapted for attachment to the bridge or bridge plate, and having portions thereof spaced from the said attachment portion and bent at an angle thereto into closely spaced parallelism to form a clasp eye for engagement with a keeper.

7. In a dental fastening, an anchor formed of hard metal wire and bent at the center to bring its intermediate portions into spaced, parallelism to form an eye closed overhead and having its end portions bent outwardly to diverge in opposite directions from the base of the eye and then bent into )arallelism said bends bein made in a plane substantially at right angles to the CHARLES W. LOKEY.

Witnesses NOMIE WELsr-r,

R. D, JOHNSTON, "Jr.

Copiesof this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. 0. 

